In most computer networks, system and network administrators use software programs, i.e., network management applications, to monitor the network and to help recognize problems with systems attached to the network. Sometimes either the network management stations or the systems on the network are misconfigured in such a way that the network management stations cannot communicate with the systems on the network or cannot determine the health of the systems on the network. Examples of such misconfigurations include: system names not matching the network addresses being used; passwords being configured differently between management stations and network nodes; and routers and switches being configured to block some network ports between the management stations and network nodes.
A conventional approach to addressing this problem is for network administrators to use various software tools to try to identify the source of the problem. For example, network administrators can use name and address resolution tools on the management station and on the network nodes to ensure that the names and addresses match; they can check passwords on both management station and network nodes to see if they match; and so on. This approach is inadequate, however, because the set of tools continually evolves (making it very difficult to administrators to know which tools are useful), and because the set of tools is different on different network nodes (making it very difficult to apply knowledge learned with one network node to another). What is needed, therefore, is a more effective way of diagnosing connectivity problems from a network management station.